In recent years, TCP/IP (Transmission Control Protocol/Internet Protocol) has been widely used as a protocol for performing communication among multiple hosts. The process for TCP/IP is performed at the time of reception and at the time of transmission, in accordance with the specification of the protocol, and it is general that this process is generally performed by the software that operates on a CPU.
In communication, the information containing an IP address, a port number, a sequence number, a window size and the like is stored in a memory, for storing the connection information in TCP. There is a limit to the area in the memory for storing the connection information, and therefore, it is necessary to reuse an area for the connection information that has been used once. On this occasion, in the connection establishment, it is necessary to allocate a memory area for storing the connection information from an unused memory area, and to initialize the connection information. In conventional communication apparatuses, these processes are performed by the CPU (Central Processing Unit).